In a letter to President Trump, Iowa Gov. Kim Reynolds, joined by the governors of Kansas, Missouri and South Dakota, expressed concern for how Environmental Protection Agency (EPA) Administrator Scott Pruitt has acted regarding the renewable fuel standard (RFS). The governors said the EPA seeking comment on cuts to 2018-2019 RFS volumes, and signaling an intent to waive volumes for 2018, showed "a willingness to upend a decision producers and other stakeholders have already relied upon to make investments, contractual commitments and create jobs." In a press conference Wednesday, Reynolds said the administration was "feeling the pressure" and that biofuel supporters "can't let down."

Following a meeting with Pruitt, Iowa Senator Chuck Grassley said he will watch the RFS "closely" and "hold the administration accountable," while Iowa Senator Joni Ernst said, "Administrator Pruitt again claimed today that he will not do anything to undermine the program. However, we have heard this before. We now need to see it." Ernst said she could not back a nominee to head an EPA office that runs the RFS without further assurances from the agency to protect the program, according to Bloomberg.